LED light fitting

[SparkyTris]

I have just bought (from a well-known electrical wholesaler and retailer) a couple of 240VAC bulkhead LED lights. I was slightly surprised at how "crap" they were given the reasonably high price I paid for them.
they are presented to the installer with L and N singles in about 1mm2 that come straight out the back of the base into a plastic enclosed terminal block.
This presentation was firstly inconvenient to me and secondly I thought less secure/safe than it could have been so I dived in for a slight modification, so that I could run the house T&E straight into the luminaire.

I then noticed that the LED carrier PCB had clearly been designed with an earth in mind, but the metallic-looking luminaire base was not earthed. I checked, and the luminaire base is indeed exposed metal.

the product is marked double insulated and evidently does not require an earth in the eyes of ... the law. ? the type-approval people?

it is CE marked

interested in comments. it looks like the sort of chinese crap that I would quite happily pay £20 a go for on ebay - caveat emptor - but less happily £55 from a reputable supplier.

I am happier now that according to physics & common sense I have a better product (resulting from my modification)
I am equally aware that I have been a naughty boy in taking the law into my own hands to modify a type-approved product and also because of this have voided any warranty or guarantee.

comments appreciated.

 

[SparkyTris]

short video pertinent to above

 

[ban-all-sheds]

comments appreciated.

OK

I am equally aware that I have been a naughty boy in making a light more dangerous than it was before

 

[SparkyTris]

I did say comments appreciated..?

ok - more dangerous - this is what I was afraid of - break it down for me B-A-S, please!

 

[ban-all-sheds]

You took an isolated piece of metal and un-isolated it.

 

[SparkyTris]

Indeed; I took said isolated and exposed piece of metal and connected it to a CPC. In its original incarnation, if a "line-to-chassis" fault had developed, the exposed metallic chassis would have become line potential and likely no disconnectors would have functioned. In its modified state, if a line-chassis fault occurs, the RCD will operate and:
A. isolate the whole circuit
B. indirectly, inform me that there is a problem.

Additionally:
I no longer have the 2 rather fragile singles running in a void. Instead I have the somewhat tougher T&E directly - and comfortably - into the lumi.

Now don't get me wrong, I do not habitually go around earthing every piece of isolated metal I find. However I do certainly think about doing so wherever isolated, exposed pieces of metal form the enclosure of an electrical device.

now you can see my potentially flawed justification/ train of thought, please can you explain to me in terms that I might understand, how I have made it more dangerous by modifying as stated?

 

[bernardgreen]

You took an isolated piece of metal and un-isolated it.

It would appear that the original designer of the lamp intended for a CPC to be connected to the metal plate. The Earth symbol in a complete circle next to the terminal block suggests this. ( google eic5019 )

 

[ban-all-sheds]

Indeed; I took said isolated and exposed piece of metal and connected it to a CPC.

But it was not an exposed-conductive-part.

the product is marked double insulated

In its original incarnation, if a "line-to-chassis" fault had developed, the exposed metallic chassis would have become line potential

the product is marked double insulated

Now don't get me wrong, I do not habitually go around earthing every piece of isolated metal I find. However I do certainly think about doing so wherever isolated, exposed pieces of metal form the enclosure of an electrical device.

But the enclosure was not an exposed-conductive-part.

the product is marked double insulated

please can you explain to me in terms that I might understand, how I have made it more dangerous by modifying as stated?

Now any L-cpc fault on the circuit will make the case of the light live until a disconnection occurs.

 

[SparkyTris]

But the enclosure was not an exposed-conductive-part.

The enclosure was and remains an exposed conductive part (or exposed-conductive-part, if the hyphens are important - or did you mean to write Exposed Conductive Part?). I think that is basically my point.

the product is marked double insulated. the product is not double-insulated. Is it? .... is it?

Now any L-cpc fault on the circuit will make the case of the light live until a disconnection occurs.

yes, for a vanishingly short period of time - the disconnection time of me bran-new RCDs in my case, the disconnect time of the circuit protection device in the wider case, be it RCBO, MCB or fuse.

prior to my mod, any L-cpc fault in the luminaire will make the case live, period. Yes ok, there was no CPC in the lumi prior to mod, but CPC==case==Exposed Conductive Part

 

[333rocky333]

Under what circumstances would this case become Live, the way its sold, the connections would be enclosed in the plastic block provided, the Driver cables look like they pass through the metal via an insulated grommet, then go in a Driver which is also likely Double insulated.
The Earth symbol on the board is from when they bolted the Connector block direct on to it, this is now replaced with the plastic remote connector block to give it Double insulated status.
Double Insulated Afaik does not forbid metal components, just that the likely hood of them becoming live is very low.

 

[SparkyTris]

Double Insulated means that there are (at least) 2 insulating layers between the user and the juice. Maybe "Air" can be one of these insulating layers. (?) somehow I doubt it.

 

[bernardgreen]

Under what circumstances would this case become Live,

When the driver cremates itself is one circumstance, The other more frequent failure more is when the insulation in the high frequency transformer in the driver breaks down. The device may still be working as a driver putting current thorough the LEDs but the previously isolated output is now connected to the mains.

 

[SparkyTris]

Under what circumstances would this case become Live

No, absolutely - it seems very unlikely that the case could become live. this is said without the benefit of the same hindsight that led to CPC conductors being installed as a matter of course. On a well-made product, it should naturally be very unlikely that the case could ever become live. but this doesn't stop us assiduously earthing the cases of - for example, washing-machines, fuseboxes, DVD players....

 

[SparkyTris]

When the driver cremates itself is one circumstance, The other more frequent failure more is when the insulation in the high frequency transformer in the driver breaks down. The device may still be working as a driver putting current thorough the LEDs but the previously isolated output is now connected to the mains.

Yes, exactly. The voice of hard practical experience there.

 

[ban-all-sheds]

It would appear that the original designer of the lamp intended for a CPC to be connected to the metal plate. The Earth symbol in a complete circle next to the terminal block suggests this. ( google eic5019 )

If there are doubts about the validity of the Double Insulated symbol, or the CE mark, the proper course of action is to take it to Trading Standards so that they can investigate.

Not doing so is a dereliction of civic responsibility, because if the lights are dangerous they should be taken off sale, not rectified by the installer but on the shelves of a well-known electrical wholesaler and retailer where they will be purchased by other people who might not carry out the rectification.